POLICY HARMONIZATION, CONVERGENCE, AND COMPATIBILITY ISSUES IN NORTH AMERICAN HORTICULTURE

Agricultural and Food Policy,

Magnetocaloric effect and improved relative cooling power in (La0.7Sr0.3MnO3/SrRuO3) superlattices

Magnetic properties of a series of (La0.7Sr0.3MnO3/SrRuO3) superlattices, where the SrRuO3 layer thickness is varying, are examined. A room-temperature magnetocaloric effect is obtained owing to the finite size effect which reduces the TC of La0.7Sr0.3MnO3 layers. While the working temperature ranges are enlarged,, -DeltaSmax values remains similar to the values in polycrystalline La0.7Sr0.3MnO3. Consequently, the relative cooling powers are significantly improved, the microscopic mechanism of which is related to the effect of the interfaces at La0.7Sr0.3MnO3/SrRuO3 and higher nanostructural disorder. This study indicates that artificial oxide superlattices/multilayers might provide an alternative pathway in searching for efficient room-temperature magnetic refrigerators for (nano)microscale systems.Comment: 14^pages, 3 figures, Submitted to J. Phys. Cond. Ma

Identification of Rigid Body Parameters Using Experimental Modal Analysis Data

A simple direct method is presented here to identify the rigid body parameters of a structure under a free-free condition using the measured vibration data and geometrical co-ordinates of the measurement points relative to an arbitrarily selected general co-ordinate system. These parameters consist of mass, co-ordinates of mass centre, mass-moment of inertia, and the corresponding required principal values and axes. The test structure should be Weakly suspended or soft mounted to ground. The rigid body motion should be carefully selected from the measured transfer functions. Practical considerations like the selection of general co-ordinate system, the measurement and excitation points, the minimum set of measurements etc, to be noted during performing the vibration tests or evaluating the rigid body parameters are illustrated with the help of three practical examples. The accuracy of the identified parameters depends, to a great extent, on these considerations. Comparisons between identified and theoretical results are also given

Current Taxonomic Status of the Plesiosaur Pantasaurus Striatus from the Upper Jurassic Sundance Formation, Wyoming

Plesiosaur material has been known from the Redwater Shale member of the Sundance Formation (Jurassic: Oxfordian) of Wyoming for over 100 years, but has received little research attention. Here we report on the taxonomic status of a long-necked cryptocleidoid plesiosaur from the Redwater Shale, the correct identity of which is Pantosaurus striatus Marsh 1893. The taxon Muraenosaurus reedii Mehl 1912 is shown to be a junior synonym of Pantosaurus striatus. Pantosaurus is described on the basis of the holotype and referred specimens, and found to be a cryptocleidoid plesiosaur possessing between 35 and 40 cervical vertebrae. These vertebrae are very similar in proportion and anatomical detail to those of Muraenosaurus leedsii from the Oxford Clay of England. However, the forelimb of Pantosaurus is diagnostic and differs from that of Muraenosaurus in several particulars, the most important being the relatively large size of the radius and its corresponding humeral articulation. Although no cranial material is available at this time, we believe that Pantosaurus striatus is a valid taxon

Preliminary Report on the Osteology and Relationships of a New Aberrant Cryptocleidoid Plesiosaur from the Sundance Formation, Wyoming

The cryptocleidoid plesiosaur Tatenectes laramiensis, new genus, is described from the Redwater Shale Member of the Sundance Formation, Narrona County, Wyoming. The holotype of this species was a partial skeleton that has since been lost. A neotype is designated that preserves the same elements present in the holotype. A second specimen is referred to the taxon, and this specimen includes cranial material. The preserved cranial elements are the left squamosal, a partial right frontal, several isolated teeth, the parasphenoid, and large portions of the left and right pterygoids. The skull shares many traits with that of Kimmerosaurus, a cryptocleidoid plesiosaur from the Kimmeridge Clay of England. However, the palate is derived, and resembles those of the poorly-understood cimoliasaurid plesiosaurs of the Creoceno of the southern hemisphere. This similarity is established via comparison with the skull of an undescribed taxoo from late Jurassic of Cuba. The cryptocleidoid plesiosaurs underwent an extensive radiation in the Late Jurassic, and more research attention is needed, beginning with additional preparation and collection of Tatenectes

Experimental Identification of Modal Density Parameters of Light Weight Structures

A basic requirement for the analysis of vibro-acoustic problems by means of the Statistical Energy Analysis (SEA) is the knowledge of modal densities of the tested subsystems. For simple structures, modal densities are obtained by theoretical solutions. The application of the SEA to complex light weight structures often leads to sophisticated subsystems the modal densities of which cannot be received from theoretical solutions. Therefore, experimental procedures for the identification of modal densities are needed. This paper describes an experimental method based on the theoretical relation between the modal density and the real part of the point admittance, the conductance. Simulations of a simply supported rectangular plate show the accuracy and the limits of the method A steel plate and a thin-walled cylinder made offiber composite material have been thoroughly investigated by experiments. By this, the influence of the mass correction of the measured conductances is discussed in the paper. The experimental results are compared with theoretical results obtained from the code AutoSEA2. For medium and higher frequencies the results are in fairly good agreement